Item Response Theory
It was well-known to classical test theorists that measurement precision is not uniform across the scale of measurement. Tests tend to distinguish better for test-takers with moderate trait levels and worse among high- and low-scoring test-takers. Item response theory extends the concept of reliability from a single index to a function called the information function. The IRT information function is the inverse of the conditional observed score standard error at any given test score.
Read more about this topic: Reliability (psychometrics)
Famous quotes containing the words item, response and/or theory:
“All of womens aspirationswhether for education, work, or any form of self-determinationultimately rest on their ability to decide whether and when to bear children. For this reason, reproductive freedom has always been the most popular item in each of the successive feminist agendasand the most heavily assaulted target of each backlash.”
—Susan Faludi (20th century)
“Love is the victims response to the rapist.”
—Ti-Grace Atkinson (b. 1938?)
“If my theory of relativity is proven correct, Germany will claim me as a German and France will declare that I am a citizen of the world. Should my theory prove untrue, France will say that I am a German and Germany will declare that I am a Jew.”
—Albert Einstein (18791955)